Immunohistochemical Loss of DPC4 in Tumors With Mucinous Differentiation Arising in or Involving the Gynecologic Tract

TP53 as a Diagnostic Aid in the Distinction of Ovarian Mucinous Borderline Tumors From Mucinous Carcinoma

Ovarian mucinous borderline tumors (MBTs) are clinically managed as benign neoplasms while the management of ovarian mucinous carcinomas (MC) is dependent on tumor stage. Despite the standardization of sampling of ovarian mucinous neoplasms, limited interobserver reproducibility between MBT and MC persists. Based on our recent finding that abnormal TP53 expression is associated with unfavorable outcome in MBT, we hypothesized that TP53 status might improve the reproducible distinction of MBT from MC. A virtual slide set of 85 consecutive ovarian mucinous neoplasms received at a single institution, with each case represented by 3 full sections, were reviewed by 3 pathologists in 2 iterations. The initial assessment was based solely on morphologic review, while the second iteration was performed with knowledge of TP53 status. The reproducibility of a trinary categorization (MBT, MBT with intraepithelial carcinoma [IEC], MC) significantly improved from a κ of 0.60 based on the initial morphologic assessment to a κ of 0.76 (t-test, P =0.0042) after consideration of TP53 immunohistochemistry (IHC) results. Six out of 85 patients died of disease, and in 2 of them, at least 1 pathologist assessed MBT with IEC and not MC even after integration of TP53 IHC. With the integration of TP53 IHC, substantial interobserver agreement for MBT and MC can be reached, particularly in cases with an uncertain degree of confluent growth. TP53 IHC can also be used to highlight and support the presence of IEC in MBT, however, discordances remained in 2 cases with adverse outcome.

Gynaecological or gastrointestinal origin? Recognising Müllerian neoplasms with gastrointestinal phenotype and determining the primary site in selected entities

Recognising metastatic gastrointestinal and pancreatobiliary tumours to gynaecological sites may be challenging, as primary Müllerian tumours can demonstrate similar histological features. Endocervical adenocarcinomas can be of gastric and intestinal types, endometrial lesions may show gastrointestinal phenotype, and finally, mucinous tumours with secondary involvement of the ovaries may mimic primary neoplasms. The aim of this review is to address selected neoplastic entities of the gynaecological tract with gastric and intestinal differentiation and provide helpful clinical and pathological parameters for the diagnosis. A brief overview of metastatic tumours originating from the gastrointestinal and pancreaticobiliary tracts is also provided, including the most common pathological features.